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Politics: Is Hinkley C dead?

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    •  
      CommentAuthorSteamyTea
    • CommentTimeAug 2nd 2016
     
    Mike
    As they say, correlation is not causation, and it does not take into account national interconnects.

    And when it does go wrong, it does it big time:
    https://en.wikipedia.org/wiki/2006_European_blackout

    The EU grid is of very different design to the UK one and I suspect that they are investing more money into it.
    •  
      CommentAuthorfostertom
    • CommentTimeAug 2nd 2016 edited
     
    From earlier on in this thread:
    Posted By: fostertomhttp://blog.rmi.org/blog_2016_07_11_closing_diablo_canyon_nuclear_plant_will_save_money_carbon

    "... removing the inflexible “must-run” nuclear output, which can’t easily and economically ramp down much, will help integrate more renewable power reliably into the grid. Midday solar, rather than being increasingly crowded out by continued nuclear overgeneration, will be able to supply more energy. As Germany found, integrating varying solar and wind power with steady “baseload” plants can present challenges for the opposite of the reason originally supposed: not because wind and solar power vary (demand varies even less predictably), but because “baseload” plants are too inflexible."
    I guess this is visible in the large %age of times that we see whole windfarms at a standstill, in all seasons - being paid to not produce so the old baseload can womble on.
    • CommentAuthorbarney
    • CommentTimeAug 2nd 2016
     
    We need the wombles to keep things stable - no amount of wishful thinking will allow connection of invertor based renewables to a grid that can't maintain frequency stability - and you need high inertia rotating plant for that

    Barney
    •  
      CommentAuthorfostertom
    • CommentTimeAug 2nd 2016 edited
     
    So what is different in Germany, that they've 'cracked it'? (Mike1 above?)
    • CommentAuthorbarney
    • CommentTimeAug 2nd 2016
     
    Neighbours with big rotating plant basically, Tom

    Whilst they have rejected Nuclear, they have no problem benefiting from the large stable nuclear capacity of the French - and of course their own filthy dirty lignite plants

    We don't have that interconnection, we have to do it ourselves - our interconnects (as I keep saying) are principally High Voltage DC links - basically invertors that need to track stable system frequency to allow conversion and import/export

    And they most certainly haven't "cracked it" - read the article correctly

    The outages have reduced marginally due to less 3rd party insults (vehicles, dig damage, station trips etc) - you need to look at the number of "interventions" required to stabilise or balance the grid - they have risen exponentially compared to the rate of increase in renewables in the last 5 years or so - the grid operators are being paid a fortune to do this

    There is no magic bullet Tom - we need a basket full of technologies - but for the foreseeable future, some of those technologies need to be big rotating plant - or we will get extensive cascade tripping as renewable plant comes off the busbars and there simply isn't enough base capacity left to stabilise to allow the invertor plant to synchronise back onto the grid

    At a simple level, if I turn off the power to a house with a few kW of PV via an invertor and a kw wind turbine , it can only operate when synchronised with the mains - loss of power trips the PV and the wind turbine - if I then have to restore power despite the wind blowing and the sun shining I can't - I have no stable frequency and voltage to synchronise either technology to - they cant synch to each other (in practice) - I have to wait for the grid to come back first - but what grid - where is that power coming from ?

    Now imagine that house is the whole SW of England - where is that power coming from ?

    Personally, I'd be happy with HPC or the Severn Barrage - just as long as it goes round and round and is big. Only when we have stability can we add those glamorous "renewables"

    In parallel of course, we need to consider just what "grid" means - we either go back to hundreds of autonomous mini grids that we had perhaps a 100 years ago - or we sort out the current grid to make it just a little bit smarter

    Principally however, the best kW is the one you don't need - we need to get the demand down and flattened out

    Regards

    Barney
    •  
      CommentAuthorfostertom
    • CommentTimeAug 2nd 2016
     
    Thanks barney - I'll re-read that and ponder - and then come back at you no doubt!
    •  
      CommentAuthordjh
    • CommentTimeAug 2nd 2016
     
    There's an interesting piece on the Chinese efforts at

    https://www.technologyreview.com/s/602051/fail-safe-nuclear-power/
    • CommentAuthorbarney
    • CommentTimeAug 2nd 2016
     
    Whilst you ponder - also consider the capability to "move" the renewable generation to where demand is - and what excess generation means for your neighbours - German industry in the south cannot really use excess generation in the north - the grid isn't arranged for that kind of transfer

    Whilst the massive wind generation in north Germany of late is considered a triumph by some, it caused severe problems for Poland resulting in them having to emergency shut down plant - and also to accept import to re export to Austria - never a good plan

    Similar problems exist with Spanish renewable generation impacting on French generation - in some cases interconnectors have needed to be opened to maintain stability

    You need to think of conventional rotating generators (Coal, natural gas, hydro, nuclear, biomass) which provide “Essential Reliability"

    You need to think of Wind and solar as creating Essential Reliability risks because they are intermittent and they do not as readily provide Essential Reliability - they create unreliability

    For assessing grid reliability, the maximum amount of wind and solar during times of stress is the key number not the “average” contribution of wind and solar - these asynchronous inputs are a massive destabilising factor

    It's also important not to confuse Grid reliability with Distribution reliability - the article touting the strength of the German grid based on measures of distribution reliability only considers loss of generation - it doesn't comment (unsurprisingly) on the grid reliability (see my previous comments about the number and cost of grid interventions)

    The "how guys" can solve this, the technology is relatively mature - but it will need a lot of investment and a long time (and no doubt piss off a few tree huggers complaining about new power lines running through the garden)

    That's basically whey we need HPC - to keep things stable whilst renewables get sorted out in conjunction with a grid designed for them rather than bolting them to a grid totally unsuited to them

    Regards

    Barney
    •  
      CommentAuthorfostertom
    • CommentTimeAug 2nd 2016 edited
     
    Posted By: barneyThat's basically whey we need HPC - to keep things stable whilst renewables get sorted out in conjunction with a grid designed for them rather than bolting them to a grid totally unsuited to them
    That's a message of some hope - and a pretty watered-down version of why Hinkley (I eventually decoded 'HPC') is essential - as a stopgap till grid technology modernises and/or grid investment catches up.

    But will that take anything like the 35yrs that taxpayer will be subsidising (Ă‚ÂŁ21bn and rising) output that sooner rather than later will be unwanted?

    Wouldn't the cost of Hinkley + that subsidy be better spent on grid modernisation and investment?
    • CommentAuthorringi
    • CommentTimeAug 2nd 2016
     
    If we had lots of wind driven pumps (not grid connected) running whenever there was wind, to refill the hydro how much would that help without needing big lakes at the bottom of the hydro stations? (E.g. never pump up faster than the water is coming down.)

    Automatic demand side management base on short term frequency changes must help a bit, what if ALL new fridges, freezers and washing machine had to reduce their demand at times of low frequency?

    If I understand correctly steam based power stations are liked so much, as there is a large short term energy storage in the steam that can be automatically call on microsecond by microsecond to stabilize the frequency. The boiler is run to keep the pressure of the steam correct over a few minutes time scale as so much steam is stored in the boiler and pipework. Therefore giving free of charge fast response short term energy storage.

    What would it take to create large inverters that outputted more power when the frequency dropped connected to “pump batteries”?

    Would any sensible person install a new AC based grid these days, rather than using HVDC with a inverter in each “substation”?

    Why does the frequency have to be so stable anyway?
    • CommentAuthorbarney
    • CommentTimeAug 2nd 2016
     
    OK - HPC Is needed to keep the lights on Tom

    It's advantage over that timeframe is it allows the changes needed to move to renewables - say 2050 - so in some regard, it is a stop gap - all generation is a "stop gap" as it has finite life

    We'll probably find someone is having this "grid" conversation in 100 years - it really will take that amount of time

    Grid modernisation doesn't produce a single kW of power (actually it's a consumer) so spending on one and not the other isn't the choice - the choice is HPC plus whatever else we need to spend

    Frequency is important for all sorts of reasons - principally (in this debate) - to allow all the small scale technologies to usefully connect to the grid

    Suggest you compare the cost of a 1MVA invertor with a 1MVA transformer - and include in that overload and fault clearing ability

    There are lots of techniques available - but does UK Plc want to pay that much for them - or do we still want cheap energy (and before anyone kicks off about the HPC strike price, look at the strike price of the Swansea lagoon - and for some offshore wind)

    Basically what do we want - and how much are we prepared to pay for it (comparatively to other parts of the world). From there, we might just get a grown up energy policy for the next century

    Barney
    •  
      CommentAuthorSteamyTea
    • CommentTimeAug 2nd 2016 edited
     
    The use of frequency for load shedding is really only useful for emergencies at the moment.
    It is often used in tiny stand alone grids, but as our national grid uses predictive generation, it is not unusual to have lower frequency at times of lowering load, and higher frequencies at times of higher load. This method is used to maintain voltage and reduce current.
    The last thing you really want is 10 million fridges turning off at the same time.

    Also, fridges are of such lower power now (<100W), you are only talking of a power reduction of about 1GW. In winter that is about 1/40th of the power being generated.
    • CommentAuthorbarney
    • CommentTimeAug 2nd 2016
     
    It's not the load shedding issue though - the small scale invertors some on here believe will save us HPC need to track voltage and frequency - otherwise they can't connect to the grid - physically can't connect

    If the grid frequency isn't stable then all this small scale stuff is banging in and out of circuit - causing further instability

    The advantage of big rotating plant is they can lock into the synchronous frequency and from there blasting in more fuel doesn't result in a speed increase, it just allows more power output - when that's all stable, then little grid tie systems can operate OK

    Most of this stuff is done specifically by vector shift monitoring or rate of change of frequency (ROCOF) monitoring - frequency is critically important

    Regards

    Barney
    • CommentAuthorringi
    • CommentTimeAug 2nd 2016
     
    Posted By: SteamyTeaThe last thing you really want is 10 million fridges turning off at the same time.


    You don’t get that if you use half a brain, one very simple system for example. The fridge checks at a random time every 10 minutes if the grid wants it to reduce its short term power usage. If so it changes the setpoint that start the compressor by 1 degree c.

    There has been lots of research on random “back off” of packet resending rates on Ethernet type networks that may be a good starting point for design concepts.
    •  
      CommentAuthorSteamyTea
    • CommentTimeAug 2nd 2016
     
    Posted By: barneyIt's not the load shedding issue though - the small scale invertors some on here believe will save us HPC need to track voltage and frequency
    I wrote a bit about this a few years back on here.
    Pointed out that you can get a situation where the tail is wagging the dog, which I think is what you are saying.

    Posted By: ringiYou don’t get that if you use half a brain, one very simple system for example.
    I went for a PhD up in Cardiff about this. One of the reason I think I did not get the position is that I pointed out starting up a few million inductive loads, even spaced at random over 20 minutes, could cause harmonics in the national grid. That could cause a change in impedance and cause SS inverters to misunderstand the state of the grid (they sense grid impedance for safety reason).
  16.  
    Posted By: barneyOK - HPC Is needed to keep the lights on Tom

    It's advantage over that timeframe is it allows the changes needed to move to renewables - say 2050 - so in some regard, it is a stop gap - all generation is a "stop gap" as it has finite life

    We'll probably find someone is having this "grid" conversation in 100 years - it really will take that amount of time

    Grid modernisation doesn't produce a single kW of power (actually it's a consumer) so spending on one and not the other isn't the choice - the choice is HPC plus whatever else we need to spend

    Frequency is important for all sorts of reasons - principally (in this debate) - to allow all the small scale technologies to usefully connect to the grid

    Suggest you compare the cost of a 1MVA invertor with a 1MVA transformer - and include in that overload and fault clearing ability

    There are lots of techniques available - but does UK Plc want to pay that much for them - or do we still want cheap energy (and before anyone kicks off about the HPC strike price, look at the strike price of the Swansea lagoon - and for some offshore wind)

    Basically what do we want - and how much are we prepared to pay for it (comparatively to other parts of the world). From there, we might just get a grown up energy policy for the next century

    Barney


    Barney

    Your comments are about 5 years out of date. We now have an obscene amount of gas fired power generation with more coming online all the time, even the mothballed plants have been dusted off and pressed into use. The coal plants originally slated for scrapping are now being mothballed "just in case". We even have a dash for interconnectors which will be built before Hinkley and providing more power than Hinkley at far lower prices. Hopefully somebody in government has finally seen the light and realised what a white elephant Hinkley is.
    • CommentAuthorbarney
    • CommentTimeAug 2nd 2016
     
    OK - I disagree actually - 5 years is nothing in terms of grid capacity, but that's your opinion.

    Plant life extension (PLEX) on existing plants is just that - a short extension - and all of this tells us that we have no energy policy in the UK other than fingers crossed let alone "greening" the grid

    Personally I have no issue with gas fired thermal generation - it's clean, cheap and reliable and it rotates - but it's not low carbon - and we have to import the gas.

    and as I keep saying, HVDC interconnects don't help grid stability

    So if UK energy policy is to abandon nuclear and we want a modicum of security then we start fracking - which I suspect may be a tad unpalatable to some - or we exploit the many hundreds of yeas of top grade coal we have left - which may be even more unpalatable to all

    Ferrybridge is shut, Fiddlers ferry is on it's last legs - so I don't see much in the way of PLEX for coal - so that only leaves gas

    Regards

    Barney
  18.  
    Government about turn in March extended coals life now with Brexit we will no longer have to comply with EU rules on closing coal plants.

    https://next.ft.com/content/3a72f256-f681-11e5-96db-fc683b5e52db

    Gas is actually going green with AD plants now being encouraged to direct inject into the grid rather than generate inefficiently on site. Next big push will be gas from excess wind and solar.
    • CommentAuthorbarney
    • CommentTimeAug 2nd 2016
     
    So - this is better than HPC then - burn more coal medium term and green the gas grid rather than the electricity grid ?

    Regards

    Barney
    •  
      CommentAuthordjh
    • CommentTimeAug 2nd 2016
     
    I wish people wouldn't post paywalled links.
    • CommentAuthoratomicbisf
    • CommentTimeAug 2nd 2016 edited
     
    Posted By: barneyOK - I disagree actually - 5 years is nothing in terms of grid capacity, but that's your opinion.

    Plant life extension (PLEX) on existing plants is just that - a short extension - and all of this tells us that we have no energy policy in the UK other than fingers crossed let alone "greening" the grid

    Personally I have no issue with gas fired thermal generation - it's clean, cheap and reliable and it rotates - but it's not low carbon - and we have to import the gas.

    and as I keep saying, HVDC interconnects don't help grid stability

    So if UK energy policy is to abandon nuclear and we want a modicum of security then we start fracking - which I suspect may be a tad unpalatable to some - or we exploit the many hundreds of yeas of top grade coal we have left - which may be even more unpalatable to all

    Ferrybridge is shut, Fiddlers ferry is on it's last legs - so I don't see much in the way of PLEX for coal - so that only leaves gas

    Regards

    Barney


    HVDC interconnection does help grid stability because it allows the exchange of electricity between asynchronous grids. I'm sure I've posted it before but here's a link to a study by the US National Oceanographic and Atmospheric Administration (NOAA) and University of Colorado Boulder: http://www.noaanews.noaa.gov/stories2016/012516-rapid-affordable-energy-transformation-possible.html

    Basically they say that given the sun is always shining or the wind blowing somewhere in a country the size of the USA, by improving the transmission of electricity across the country by means of an HVDC grid, it would be possible for the USA to generate most of its electricity from renewables without raising costs (or even driving them down).

    Now the UK is too small for that, but similar should be able to apply to Europe.

    It's interesting to me because these type of discussions are usually based on back of fag packet calculations or trite observations such as that the wind doesn't always blow (in a single place), but here's a study that actually has some substance.

    Ed
  22.  
    Posted By: barneySo - this is better than HPC then - burn more coal medium term and green the gas grid rather than the electricity grid ?

    Regards

    Barney


    As already said we have no need for coal as gas capacity has already been increased to cover the demise of coal. Coal is just the insurance policy for the 1 in 100 year cold snap. At present its not economic to store electric and really theres no need when the infrastructure is already in place to store gas and generate on demand using gas. What needs to be put in place is the conversion of excess wind and solar into gas instead of being wasted at present.
    • CommentAuthorbarney
    • CommentTimeAug 2nd 2016
     
    OK - I'll take a look Ed - although I think it's more about moving here the power to the load centres rather than stability based on the mix of synchronous and asynchronous generation

    Personally I'm not sure we should be heading for a system that turns high grade energy back into low grade energy for transmission/storage and then back to high grade energy to further conversion to low grade again for heating

    Regards

    Berney
    •  
      CommentAuthorfostertom
    • CommentTimeAug 2nd 2016
     
    Posted By: renewablejohnconversion of excess wind and solar into gas instead of being wasted at present
    Now yer talking
    •  
      CommentAuthorfostertom
    • CommentTimeAug 2nd 2016
     
    Don't tell me that with a fraction of the Hinkley billions UK couldn't quickly revive renewables (tell the counties that more windmills are War Effort), grab everything autonomous that Tesla etc have got, re-engineer a lower-duty but smart grid to suit, get serious about demand reduction. OK power cuts and outages maybe - all the more urgency to push ahead.
    •  
      CommentAuthorSteamyTea
    • CommentTimeAug 2nd 2016
     
    I heard a bit on the radio from our PM May saying that she wants energy to be secure and affordable.
    So gas it is till the next general election.
  27.  
    Bear in mind the interconnectors to both Norway and Iceland will not be dependent on Wind or Solar but hydro and Geothermal.

    National Grid have a stated minimum 10% interconnect policy.
    • CommentAuthorbarney
    • CommentTimeAug 2nd 2016
     
    We are just buying power Tom - it's not the UK spending the billions - we don't have money (spent it on Trident successor)

    Gas for cheapness and fracking for security - business as usual

    Back to Maggies dash for gas

    Barney
    • CommentAuthorbarney
    • CommentTimeAug 2nd 2016
     
    They may not be asynchronous at source - they will be this end however

    Barney
    •  
      CommentAuthorfostertom
    • CommentTimeAug 3rd 2016
     
    Posted By: barneyWe are just buying power Tom - it's not the UK spending the billions - we don't have money (spent it on Trident successor)
    Don't understand that, unless it's deep stuff about what money is, who prints it into existence etc?

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